Gymnasticator



A. C. HANSON Aug. 15, 1950 GYMNASTICATOR 2 Sheets-Sheet 1 Filed April 2, 1945 H mm E INVENTOR. ARTHUR C. HANSON BY QaW MJZD-MM ATTORNEYS A. C. HANSON GYMNASTICATOR 2 Sheets-Sheet 2 Filed April 2, 1945 IIIIII'I .N m m Q WA 8 m N T u RV A 6 ATTORNEYS Patented Aug. 15, 1950 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

The present invention relates generally to apparatus for testing and/or exercising mechanisms prior to their installation in the assemhlies in which they areintended to function or prior to their release for work and constitutes a continuation-in-palt of my copending application entitled. Hydraulic Gymnasticator Serial No. 415,248, filed October 16, 1941, now abandoned.

More specifically it concerns itself with that type of apparatus which has come to be known to the art as a gymnasticator.

In devices of the type herein contemplated, those heretofore known have not, to my knowledge, been adapted to produce in the-particular mechanism being exercised the exact cycle of operation which that mechanism will execute when at work in the capacity for which it is intended. Rather, previously known gymnasticators have in the main operated the mechanism being gymnasticated according to their own set i and predetermined cycles. I have found that the purpose of a, gymnasticator is served much more effectively and einciently if it is so constructed as to be adapted to produce in the mechanism which it is currently gymnasticating a, cycle of operation similar to that which the said mechanism will executewhen actually at work.

Means for gymnasticating artillery recoil mechanisms have been my chief concern and I have found that-by providing a device adapted to impart to a given recoil mechanism movements which are of substantially the same velocity and intensity as those which will be imparted to it when the gun which it is to carry is fired, I am able not only to determine in a general way that all parts are operable and intact but I am able to determine whether or not the particular mechanism is within tolerances in all respects and whether it is capable of withstanding the stresses to which it will be subjected when in use in the field, thus avoiding the necessity for proof, firing.

It is therefore an object of this invention to provide a gymnasticator which is adapted to impart to the mechanism which it is designed to exercise and test movements similar in substantially all particulars to those which said mechanism will execute when at work in the capacity fyfOI which it was produced.

A more specific object of this invention is to z provide a gymnasticator adapted to produce in artillery recoil mechanisms a cycle of operation similar to that which said recoil mechanisms will carry out when attached to and used with artillery pieces. a

A further object of this invention is to provide a gymnasticator which is adapted to impart motion through fluid means to the mechanism which it is gymnasticating.

Other objects of my invention will become apparent as this disclosure proceeds and include the provision of novel gymnasticator structure- In general my invention in its preferred form comprises means for building up a fluid pressure head, means for rapidly releasing the pressure in said head and directing it into a mechanism which is to be gymnasticated, and means for timing the continuance of the subjecting of said mechanism t the pressure from said pressure head. Also preferably included is means for releasing the pressure built up in the mechanism as a, result of its having been in communication with said pressure head.

In order to make a clear and concise explanation of my invention, I have accompanied this specification with drawings which form a part hereof and in which:

Fig. 1 is a side elevational view of a preferred, embodiment of my invention, many parts being represented schematically;

Fig, 2 is a vertical sectional View of a, preferred form of pressure switch employed in the assembly shown in Fig. 1; i

Fig. 3 is a, view similar to Fig. 1 and showing a modified form of my invention; and

Fig. 4 is a vertical sectional view of a pressure release valve employed in both of the embodiments of my invention disclosed herein taken on line 4-4 of Fig. 1.

As previously indicated, I have chosen to describe my invention in conjunction with the recoil mechanism of an artillery piece and as a gymnasticator for. such a recoil mechanism. One of the oustanding characteristics of the action of such a recoil mechanism when in operation as a part of a firing artillery piece is its extremely rapid and forcible initial recoil. This initial recoil is followed by continuing recoil movement of a gradually decreasing intensity and speed. When the end of the recoil stroke has beem reached the counterrecoil phase of the cycle commences and includes, again, a relatively rapid and forcible initial movement followed by motion in the same direction but of gradually decreasing intensity and speed until the mechanism has returned to its initial or battery position. The initial movement in counterrecoil is, of course, not comparable in speed or intensity to the corresponding motion in the recoil phase.

I have provided an accumulator It! in which I build up a. very substantial .fluid pressure by means such. asa rotary pump .11 (Fig. '1) orra triplex piston pump '12 (Fig.3). As shown in both assemblies of the drawing, the fluid under pressure in the ccumulator is introduced through suitable conduit and valve structure-into an artillery piece recoil mechanism, such a mechanism being shown fragmentarily at.- 13. in the drawing and including a piston-ma cylinder i5, and a counterrecoil cylinder 1'6.

As shown in Fig. 1 particularly, the' accumu lator I is connected to a dry nitrogen source such as a conventional pressure-storage tank. l-1

through a conduit Ills-having adjacent the accumulator a shut-off valve 19 for disconnecting the tank :1 T from-the accumulator after nitrogen has been introduced"*ihtofthe "accumulator. YIt fwillgof course, be clear that any inert or" other suitable gas may be' employed instead of nitrogen. .Theqpump il takes oil from a. reservoir j '46 and. forces it' to. the accumulator mthrough 'conduitstructure 2a. "The. pump is actuated'by a motor'or'otherrsuitable power source 2i. In-

cluded in the'fico'ndu'it 2B a pressure. relief xvalvei'zz and a check creme-way valve 23. A -'pressure-operated,' pistonitypaswitch 24 is .in communicationiwithaccumulator ill and is thus responsive to the pressure-within" conduit 29. This switclr24 may 'loe'ilocated anywhere between valve 23 the'accumulator i0, and hydraulic'valve '21, subsequently described. Connecting the laccumulat'or'with the recoil mechanism i3 is other conduit structure 25 whichmay, "if "desired, com- ..mun'icate' with-the accumulator 'loithrough 'a [means common 'withtheconduit '20 such, for example, as a ,pipe 25. Interposed in the conduit25 is a quick acting,'solenoid operated hydraulic valve 21, the purpose and functioning 'of which will "bemade more clear hereinafter. .QAlso connected to 'the conduit structure 25 at a juncturepointbetweenthe valve 2'! and the recoil. mechanism I 3 is .a pressure release valve 28*which is interposed ina return conduit 29, the latter being dire'etly'tconnected to the conduit 25 at one end "and communicating with "reservoir" 46 iat"its"dther end. The details of release valve 28' are particularly illustratedv in Fig. 4. It will be noted that one end'o'f 'con- "unit 25 connects directly into the :cylinder I vof the recoil mechanism through suitable fitfftings.

In order to causetheiparticular gun. recoil mechanism with whichlIhaveibeen mainly concerned to execute a .cycleiofoperati'on compa- 'rable to. that which it will"'execute when in use -in the field, it 'has'been' necessary, by wayof example, to have a pressure of approximately "2500 pounds "in the" accumulator H1 at the time said accumulator. is "placed in fluid communication with the "recoil mechanism for the purpose oflgymnasticating the latter. In this particular set-up thequantity" of oil-required.,per minute approximately two and'one-half gallons. To insure'that 'thevalvefi'2'! and the 'valve' 28 ;wi11 alwaysbe in"the desired relative positions,

vnamely, the one openwh'en the other is closed, have connected"a'control'rod 30 of the valve "'21 to aicontr'ol rod' 3! of the 'valve"28 through a T'suitable lever and linkage such as 32. .Also

operatively "connected to "-the' control rod 30 of valve 21 is the plunger of a solenoid 33 adapted to open said valve when energized. A spring 34 is provided for maintaining the valve 21 in a normally closed position and its size is such as 5 enable it, through the linkage 32 and control arm 3|, to operate the valve 28 for maintaining theilatterlin'a normally: openzpositi'on. In order to render the solenoid 33 and hencethe operation of the valve 2! responsive to the pressure ClOHivithin the accumulator ID, the pressure switch -24 is operatively connected as previously described. In the particular arrangement discIQ'sed in Fig. 1 a combination transformer and rectifier 35 of conventional design is connected into'the electrical circuit including lines 36 and ?the.-'swi tch 24 to transform the 110-volt 60-cycle alternating current of lines 3'! into 6-volt direct current. Also connected into the circuit in cluding the conduits 35 and the switch 2-4 is a condenser 38, a variable resistance 39, and a supersensltive -relay' 4B. The contact points of the supersens'itive -relay ii! are connected into-an electrical circuit which includes a power :relay 4| and those of the power're1ay-4tare connected 5 into theelectrical circuit including conduits 42 which supplies the solenoid'Bi-l. Thuswhen adequate pressure has been built'up in theaccumu- 'lator' "l D'bythe pump H; say, for example,"2500 s. i., the switch' 24,"being-set to operate at thisjpredeterminedpressure, "closes contacts 43 and 44,- causing the supersens'itive're'lay dfl to energize 'the'power relay 4'! which in turn causes operation of the solenoid 33 thus opening'valve "21' and closing valveZB. By th-is'operation the *fluid' in accumulator l0 -whic'h has been stored at very high pressureis' sud'd'enly 'permitted-t0 act againstthe piston =l4=of the-"recoil mech- "anism I3 causing the same to'travel in recoil ratian" "intensity and speed comparable with that ofactualoperation. "Inthe particular assembly which I have shown, 'thecontacts 43 and 44 are ibroken substantially immediately "after the in- "itial pressure'drop in the accumulator '10- due to :"retraction of a plunger W5 in the switch 24. 45 However, 'the"valve"2l is "not immediately closed "and thevalveZB"openedas a result of action of the spring 34, since the condenser" 38 continues "to' dis'c'harge thereby energizing the 'supersensi- "tivie relay 40 fora predetermined time after the "breaking ofthe contacts wand 44, said 'predetermined time being variable by-adjustment of the resistance 39. The period of recoil of the :particular mechanism 13 being approximately three-quarters of a second,- the resistance 39, in

5 the assembly' herein' illu'strated; is so-set thatithe contacts or the supersensiti-ve relay lflwill be retained closed for approximately three quarters "of a second 'as aresult o'f' the combined action ofthe closing of the contacts 43 and M and of go thecondenser 38. 'The pressure in the accumulatofbeingsomewhat' less afterthe initial discharge and graduallydecreasingas' the valve zl 'continuesto remain open, the desired action of the piston i 4 "moving gradually slower and with less intensity in recoil after the initial movement is afforded.

The mechanism l3 having'been thus placed in "recoil position, counterrecoil action is afforded by the compressed-"nitrogen in thecounterrecoil 7 orrecuperato'r chamber 16 in the same manner -as'*wh'enthe mechanism is attaohed to a :firing gun. This action'is permitted, since the con- =denser ceases to energize" the supersensitive relay 40 at approximately the same'time the end of the recoil stroke of the mechanism isreached.

makers 62 and 63.

The valve 21 is closed and the valve 26 is opened at that time as a result of the action of the spring 34 so that the oil which has been forced into the chamber I by the accumulator is free to discharge therefrom out through a portion of the conduit and then through the conduit 29 and the valve 28 to the oil reservoir 46 from whence it returns to the sump of the pump ll. When the accumulator has again reached the predetermined pressure, the operation is repeated.

A gage 41 is shown as connected to the recuperator chamber l6 of the mechanism for indicating the pressure therein and a gage 46 is .shown as connected to the accumulator for inpressed condition. Electrical contacts 43 and 44 are mounted in a plug 56 inserted in a piston cap 51 and are preferably longitudinally slidable in said plug 56 within limits. Springs 58 and 59 which are also electrical conductors are adapted to retain said contacts in predetermined normal positions and to connect them with conductors 36. A bar 66 on the face of the piston is an electrical conductor adapted to close contacts 43 and 44 when piston 45 has been forced upwardly in cylinder 5|, as a result of pressure in the accumulator ID, to a point such that said bar 60 is in engagement with contacts 43 and 44.

In the modified embodiment shown in Fig. 3,

, a large number of the components are the same as in Fig. l as will be apparent from corresponding reference characters. However, I have disclosed certain refinements which may be desirable in some assemblies. For example, a bellows type pressure switch 6i mounted, in this instance, on the top of the accumulator In, replaces the pressure switch 24 and is provided with a plurality of simultaneously operable contact The contact maker 62 is adapted to close the circuit including a power source 64, a resistance 65, and a solenoid 66 which has a plunger 61 carrying a contact maker 68 "adapted to close another circuit which inis provided adjacent one end of the solenoid 66 but spaced therefrom by a suitable nonmetallic shim H for maintaining a magnetic field adapted to hold the plunger 61 in retracted position for a predetermined time after the circuit maker 62 ceases to close the circuit which includes the solenoid 66, whereby the circuit maker 68 is maintained in operative position for an extended time and the solenoid 33 continues to be energized. The resistance 65 enables variation in the effective period of the copper ring 10. A hand switch 12 is provided for optionally cutting out the circuit maker 68 and another hand switch 13 is provided for enabling manual control of the energizing of the solenoid 33. Circuit maker 63 is also adapted to close a circuit which includes a power source 14, a resistance 15, and a solenoid 76. The solenoid 16 is provided with a plunger Ti operatively connected to a circuit breaker 18 through insulation 19. The circuit iii) breaker 18 normally closes the circuit of the motor "2| which drives the pump I2 and closure of the that the time delay effected by the ring is substantially equal to that effected by the ring III.

In exercising the particular recoil mechanism heretofore referred to I have found it expedient to regulate my gymnasticator in such manner that the drop in pressure in the accumulator does not exceed approximately four percent. Also, in order to make the action more nearly conform to that of the mechanism when a firing artillery piece is attached, in addition to regulating to three-quarters of a second the time during which the valve 21 is open and the accumulator is in communication with cylinder 15 of the recoil mechanism, I have adjusted my device so that the period during which the valve 21 remains closed, (in other words the period from the end of one recoil movement to the commencement of the next recoil movement), is approximately twenty seconds. Such adjustments may vary even for a particular type of mechanism and will necessarily vary with the different types of mechanisms being gymnasticated. If desired, a

conventional floating piston or suitable substitute may be inserted in the accumulator Ill be- I tween the gas and the liquid.

My novel process for exercising a mechanism comprises, in its preferred form, the building up of a fluid pressure adequate to accomplish the actuation of the particular mechanism involved in accordance with the normal cycle of said mechanism and subsequently introducing said fluid into the said mechanism whereby said mechanism is caused to execute said cycle. Usually but not invariably my process will be accompanied by a further step, namely, that of causing or permitting, as the case may be, said fluid to mainly discharge from said mechanism. In instances such, for example, as that of recoil mechanisms, Where the mechanism being exercised has a static or normal position, it is, of

course, necessary to supply energy for duplicating only that portion of the cycle of said mechanism which places it in maximum unstable position, after which the outside force being applied will normally be removed or released permitting the unit to return to equilibrium of its own accord.

It is not positively essential to my process that the energy be accumulated into a head before being applied to the mechanism being gymnasticated; instead, if equipment of adequate size,

, power, and, if necessary, variability is available it may be used to drive the mechanism directly. If the energy is accumulated it need not necessarily be in the form of fluid under pressure and while, as previously indicated, I distinctly prefer 

